Feature Request: Audio/Video scrubbing (Mac Camtasia 3)

Audio/Video scrubbing, please. I know this isn't new a new request (not by a long shot), but that's part of the frustration. I'm still trying to figure out why I needed to buy Camtasia 3 as I can't for the life of me see anything new (it's pretty, sure. But I'd rather have functionality).

How is it possible that users have been asking for at least four years for this essential, and very basic, feature to be added and it still hasn't been? And now you want me to pay $99 to upgrade to Camtasia 3 but still haven't managed to give us this?